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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11846

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    Protoplast production and isolation from Etlingera elatior
    (Acta Scientiarum. Agronomy, 2012-01) Otoni, Wagner Campos; Silva Júnior, Jessé Marques da; Paiva, Renato; Campos, Ana Carolina Atala Lombelo; Rodrigues, Marcelo; Carvalho, Milene Alves de Figueiredo
    The technique of hybridization using plant protoplasts is widely used in plant breeding programs. The purpose of our study is to further characterize the process of protoplast isolation from the ornamental species Etlingera elatior (Jack) R. M. Smith. Protoplasts were isolated from different tissues: in vitro leaves, in vitro pseudostem, and leaves from plants cultivated hydroponically. We tested six enzymatic combinations, four incubation time periods, the rotary system (40 rpm) or steady in the dark, and three concentrations of mannitol (0.5, 0.6 and 0.7 M). The diameter and viability of obtained protoplasts were evaluated. The best source of explants used for protoplast isolation was the in vitro leaves, which yielded 22x105 protoplasts g-1 of fresh matter. The optimal incubation period was 15 hours. The in vitro leaves presented a greater viability (96%) and larger protoplasts (36.7 µm diameter). Greater yields were obtained using a rotatory system with protoplasts incubated in the dark. The best enzymatic combination was 3% Cellulase Onozuca R-10 + 2% Meicelase + 1% Driselase + 1% Dextran + 5 mM MES, followed by the addition of 0.6 M mannitol.
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    Bromeliaceae do Parque Estadual da Serra do Rola-Moça, Minas Gerais
    (Rodriguésia, 2010-07) Guarçoni, Elidio Armando Exposto; Paula, Cláudio Coelho de; Costa, Andrea Ferreira da
    O Parque Estadual da Serra do Rola-Moça localiza-se na porção centro-sul da Cadeia do Espinhaço, na região denominada Quadrilátero Ferrífero, nos municípios de Belo Horizonte, Brumadinho, Ibirité e Nova Lima. Apresenta como vegetação os Campos Rupestres ferruginosos e quartizíticos, Floresta Estacional Semidecidual e Cerrado. O presente trabalho teve como finalidade estudar a florística da família Bromeliaceae no Parque Estadual da Serra do Rola-Moça. Foram identificadas 25 espécies pertencentes a 11 gêneros, sendo Dyckia o gênero mais representativo em espécies. Eduandrea selloana, Cryptanthus schwackeanus, Dyckia consimilis, D. densiflora, D. macedoi, D. simulans, D. schwackeana, D. trichostachya, Vriesea longistaminea e V. minarum encontram-se citadas na Listas das Espécies da Flora e da Fauna Ameaçadas de Extinção do Estado de Minas Gerais. Neste trabalho optamos por revalidar Dyckia oligantha.
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    Bambuseae (Poaceae, Bambusoideae) no município de Viçosa, Minas Gerais, Brasil
    (Hoehnea, 2016-07) Parma, Daniele de Freitas; Vinícius-Silva, Ronaldo; Machado, Evandro Pianissola; Santos-Gonçalves, Ana Paula
    O presente estudo consiste em um levantamento florístico dos bambus lenhosos (Poaceae: Bambusoideae: Bambuseae) ocorrentes no Município de Viçosa, Zona da Mata mineira. Foram realizadas expedições a fragmentos florestais no Município, no período de fevereiro/2011 a março/2015. São reconhecidos nove táxons pertencentes a dois gêneros Chusquea (duas spp.) e Merostachys (sete spp.). São apresentadas chaves de identificação, descrições, comentários sobre os táxons levantados e o estado de conservação de cada espécie é examinado. É registrada, pela primeira vez, a ocorrência de Merostachys skvortzovii para o Estado de Minas Gerais. Merostachys tatianae, espécie até agora considerada endêmica para o Parque Estadual do Rio Doce, é registrada como ocorrente em outra localidade no Estado. O presente estudo evidencia uma alta diversidade de espécies de Bambuseae na área estudada.
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    Growth regulators, culture media and antibiotics in the in vitro shoot regeneration from mature tissue of citrus cultivars
    (Pesquisa Agropecuária Brasileira, 2010-07) Oliveira, Maria Luiza Peixoto de; Silva, Crislene Viana da; Otoni, Wagner Campos; Costa, Marcio Gilberto Cardoso
    The objective of this study was to evaluate the effects of 6-benzylaminopurine (BAP) and α-naphthaleneacetic acid (NAA) combinations, basal media and beta-lactam antibiotics on in vitro organogenesis from mature stem segments of 'Pêra', 'Valência' and 'Bahia' sweet oranges and 'Cravo' rangpur lime. For induction of shoot regeneration, the segments of the four cultivars were placed on Murashige and Skoog (MS) medium containing the following BAP/NAA concentrations: 0.0/0.0; 0.25/0.0; 0.25/0.25; 0.5/0.0; 0.5/0.5; 1.0/0.0; 2.0/0.0; 2.0/0.25; 2.0/0.5; and 2.0/1.0 mg L-1. In order to test the influence of the culture media on shoot-bud induction, (MS), Murashige and Tucker (MT), and woody plant medium (WPM) formulations were evaluated, associated with the best combination of plant growth regulators obtained in the previous experiment. The influence of four beta-lactam antibiotics (timentin, cefotaxime sodium salt, meropenem trihydrate and augmentin) on shoot regeneration was determined. Better regeneration responses were achieved when internodal segments were cultured onto MS-based medium with 500 mg L-1 cefotaxime with the following BAP/NAA concentrations: 0.5 + 0.25 mg L-1 for 'Cravo', 1.0 + 0.25 mg L-1 for 'Valência' and 'Bahia', and 1.0 + 0.5 mg L-1 for 'Pêra'. Genotype, growth regulators, basal media and beta-lactam antibiotics affect the morphogenetic response in mature tissues of citrus.
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    Photosynthetic induction and activity of enzymes related to carbon metabolism: insights into the varying net photosynthesis rates of coffee sun and shade leaves
    (Theoretical and Experimental Plant Physiology, 2013) Martins, Samuel Cordeiro Vitor; Detmann, Kelly Coutinho; Reis, Josimar Vieira dos; Pereira, Lucas Felisberto; Sanglard, Lílian Maria Vincis Pereira; Rogalski, Marcelo; DaMatta, Fábio Murilo
    The shade leaves of coffee (Coffea arabica L.) apparently retain a robust photosynthetic machinery that is comparable to that of sun leaves and can fix CO2 at high rates when subjected to high light intensities. This raises the question of why the coffee plant would construct such a robust photosynthetic machinery despite the low photosynthetic rates achieved by the shade leaves at low light supply. Here, we grew coffee plants at 100% or 10% full sunlight and demonstrated that the shade leaves exhibited faster photosynthetic induction compared with their sun counterparts, in parallel with lower loss of induction states under dim light, and were well protected against short-term sudden increases in light supply (mimicking sunflecks). These findings were linked to similar photosynthetic capacities on a per mass basis (assessed under nonlimiting light), as well as similar extractable activities of some enzymes of the Calvin cycle, including Rubisco, when comparing the shade and sun leaves. On the one hand, these responses might represent an overinvestment of resources given the low photosynthetic rates of the shade leaves when light is limiting; on the other hand, such responses might be associated with a conservative behavior linked to the origin of the species as a shade-dwelling plant, allowing it to maximize the use of the energy from sunflecks and thus ultimately contributing to a positive carbon balance under conditions of intense shading.
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    Phytochemical characterization and effect of cagaita leaf extracts on Aspergillus Sp.
    (Floresta e Ambiente, 2019) Malheiros, Rafael Pozzi; Santos, Florisvalda da Silva; Machado, Luciana Lucas; Mapeli, Ana Maria
    Fungi of the genus Aspergillus may promote damage to the physiological quality of forest seeds, and plant extracts have been used to control microflora associated with these seeds. Thus, the aim of the present work was to perform the phytochemical characterization of ethanolic and aqueous extracts obtained from Eugenia dysenterica leaves (cagaita), as well as to evaluate the effect of these extracts on the development of Aspergillus sp. isolated from Hymenaea stigonocarpa seeds (jatobá-do-cerrado). For this, qualitative phytochemical analysis of extracts was carried out and their effect on Aspergillus sp mycelial growth, sporulation and spore germination was evaluated. As a result, phenols, hydrolysable tannins, flavonols, flavanones, xanthones, flavones, free steroids and saponins were found in both extracts, which could be used in the search for new antifungal compounds in the treatment of stored forest seeds, since extracts have secondary compounds that allow inhibiting Aspergillus sp mycelial growth.
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    Heat unit accumulation and inflorescence and fruit development in ‘Ubá’ mango trees grown in Visconde do Rio Branco - MG
    (Revista Brasileira de Fruticultura, 2018) Lemos, Lorena Moreira Carvalho; Salomão, Luiz Carlos Chamhum; Siqueira, Dalmo Lopes de; Pereira, Olinto Liparini; Cecon, Paulo Roberto
    There are little information in the scientific literature on flowering and fruiting of ‘Ubá’ mango trees. These information enables to know the proportion of hermaphrodite flowers in inflorescence, fruit set percentage and developmental stages of the fruit. In this study evaluations on inflorescence and fruit development of the ‘Ubá’ mango tree (Mangifera indica L.) were carried out, as well as the determination of the required number of heat units for full fruit development. Thirty branches whose terminal buds were swollen were selected from five mango trees. With the aid of a camera and a caliper, the panicle and fruit development were evaluated weekly until full fruit development. A digital thermometer was used to record ambient temperatures during fruit development in order to estimate the number of heat units required for complete development of the fruits. Male and hermaphrodite flowers of the panicles were also identified and counted. The developmental cycle of ‘Ubá’ mango from the beginning of apical bud swelling to commercial harvest of the fruit lasted 168 days in 2011 and 154 days in 2012. The number of hermaphrodite flowers and the percentage of fruit set in the inflorescence in 2011 were 32.3 and 0.066%, respectively; and 122.1 and 0.099% in 2012, respectively. There was accumulation of 3,173 heat units from flower bud swelling to full development of the ‘Ubá’ mangoes.
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    Leguminosae no Parque Ecológico Paulo Gorski, Cascavel, Paraná, Brasil
    (Rodriguésia, 2012-10) Garcia, Flávia Cristina Pinto; Snak, Cristiane; Temponi, Lívia Godinho
    Este estudo apresenta um levantamento florístico da família Leguminosae no Parque Ecológico Paulo Gorski, uma reserva natural no oeste do estado do Paraná, sul do Brasil e teve como objetivo contribuir para o conhecimento da flora de leguminosas no estado. As coletas ocorreram mensalmente, entre outubro/2007 e dezembro/2008, ao longo de trilhas preexistentes. Leguminosae foi representada por 29 espécies, alocadas em 26 gêneros. Senna foi o gênero mais representativo, com três espécies, seguido por Desmodium, com duas espécies. Os demais gêneros foram representados por uma única espécie. Este trabalho inclui chave de identificação, descrições, comentários, distribuição geográfica, fenologia e ilustrações das espécies.
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    As Leguminosae arbóreas das florestas estacionais do Parque Estadual do Itacolomi, Minas Gerais, Brasil
    (Rodriguésia, 2010-07) Garcia, Flávia Cristina Pinto; Lima, Laura Cristina Pires; Sartori, Ângela Lúcia Bagnatori
    Este estudo consiste do tratamento taxonômico das Leguminosae arbóreas das florestas estacionais do Parque Estadual do Itacolomi (PEI). As coletas de material botânico ocorreram mensalmente, entre setembro de 2004 e novembro de 2005, ao longo de oito trilhas distribuídas em áreas de florestas estacionais submontana, montana e altimontana. O levantamento resultou em 39 táxons reunidos em 22 gêneros e distribuídos entre as três subfamílias: Caesalpinioideae (9 espécies), Mimosoideae (17) e Papilionoideae (13). Os gêneros mais representativos foram Inga (8 espécies), Machaerium (4), Senna e Dalbergia (3, cada), Abarema, Anadenanthera e Tachigali (2, cada). Bauhinia, Cassia, Copaifera, Melanoxylon, Calliandra, Mimosa, Piptadenia, Pseudopiptadenia, Stryphnodendron, Andira, Bowdichia, Ormosia, Platypodium, Pterocarpus e Swartzia apresentaram uma espécie cada. Ormosia friburgensis e Tachigali friburgensis são registradas pela primeira vez para o estado de Minas Gerais. São fornecidos chave de identificação, descrições, ilustrações, dados fenológicos, comentários taxonômicos e preferência por habitats de cada táxon no PEI.
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    Miscellaneous new species in the Brazilian Bromeliaceae
    (Rodriguésia, 2010-01) Ribeiro, Otávio B. C.; Leme, Elton M. C.; Fraga, Claudio Nicoletti de; Kollmann, Ludovic J. C.; Brown, Gregory K.; Till, Walter; Machado, Marlon C.; Monteiro, Fernando J. S.; Fontana, André Paviotti
    From 1990 to 2006, 2,875 new angiosperm species were described in Brazil, including 280 newBromeliaceae species. This publication rate is considered to be a useful indicator of floristic richness andalso reveals the huge gaps in our knowledge of species that make up Brazilian biomes and the importanceof taxonomy as a basic tool to assess biodiversity and conservation. The goal of modern taxonomists is ina race against time ordained by an unprecedented rate of global biodiversity loss, and therefore collaborationis vital to successfully close these gaps. This paper is the result of a broad cooperative research effortundertaken specifically to provide basic data on the identity of new components of Brazilian biologicaldiversity. The authors describe and illustrate 22 new Bromeliaceae species from three subfamilies: Bromelioideae - Aechmea guaratingensis, A. paratiensis, A. rubroaristata, Cryptanthus capitellatus, C. venecianus, C. viridovinosus, Hohenbergia aechmeoides, H. arcuata, H. barbarespina, H. reconcavensis, Nidularium alegrense, Orthophytum teofilo-otonense, O. cearence; Pitcairnioideae - Dyckia espiritosantensis, D. nana, Pitcairnia capixaba; Tillandsioideae - Tillandsia castelensis, Vriesea euclidiana, V. fontanae, V. multifoliata, V. sanctateresensis and V. teresopolitana.